Computer account has been deleted before 2-3 weeks and we have full AD System Discovery scheduled weekly basis. So it should have been reflected in SCCM console.

My thought process was, AD system discovery will not identify deleted computers OU. If computer is alive then it will get the update of OU information via System Group Discovery. But since computer is dead and also not available in AD, OU information related
to that computer object will not get modified. Hence it will show in the OU based collection.

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